ACiQ PC06

What does ACiQ PC06 mean?

PC06 is a compressor discharge temperature protection fault. When the compressor discharge temperature (TP) exceeds 115°C for 10 seconds, the compressor ceases operation and does not restart until TP drops below 90°C. This protects the compressor from overheating, which is often driven by low refrigerant charge or a sensor problem.

Symptoms

• PC06 shown on the display
• Compressor stops running and restarts only after cooling down
• Repeated protection cycling under load
• Possible signs of a refrigerant leak

Common causes

• Low refrigerant charge or a refrigerant leak
• Faulty or miswired compressor discharge temperature sensor
• Out-of-range discharge sensor resistance
• Faulty outdoor main PCB or high-pressure valve assembly

Diagnostic steps

1. 01

   Confirm the high discharge temperature

   Check whether the compressor discharge temperature is actually above 115°C.

2. 02

   Check for refrigerant leakage

   If discharge temperature is high, inspect for leaks; stop any leak and add refrigerant as needed.

3. 03

   Verify the sensor wiring

   Confirm the discharge temperature sensor and PCB are connected per the wiring diagram and correct any wiring fault.

4. 04

   Measure the sensor resistance

   Measure the discharge sensor's resistance against the appendix; replace the sensor if the value is not normal.

5. 05

   Replace board or valve

   If the fault remains, replace the outdoor main PCB, and if it still persists, the high-pressure valve assembly.

When to call a professional

PC06 frequently traces to low refrigerant, and leak repair and recharging require EPA certification and recovery equipment. Sensor and board work happens around capacitor-charged outdoor electronics. Always contact a licensed HVAC technician for PC06; refrigerant handling, discharge-sensor testing, and replacement of the board or pressure valve must be carried out by a qualified professional.